What do you wear when your grandmother-in-law is celebrating 60 years on the throne with a river pageant on the Thames? A nautical-ish pleated number, naturally! This dress first appeared in Alexander McQueen's pre-fall 2011 collection--without sleeves. It was customized (sleeves added and the hemline lowered a few inches) to be royalty-ready, and Kate added a few of her own signature finishing touches: A matching red Sylvia Fletcher hat from James Lock & Co., and her favorite go-to shoes, nude pumps by L.K. Bennett.

Check out a closer look of the haute hat:

Pretty perfect for the occasion, right? What do you ladies think of Kate's latest look? Are you excited to see what she wears for the rest of the jubilee festivities? Discuss!